Interconnected cam plates for operating chasers and work guide means



1956 B. G. BJAL 2,760,213

INTERCONNECTED CAM PLATE OR OPERATING I CHASERS AND WORK GUIDE MEANSFiled June 30, 1955 4 Sheets-Sheet l INVENTOR.

Aug. 28, 1956 B. G. BJALME INTERCONNECTED CAM PLATES FOR OPERATINGCHASERS AND WORK GUIDE MEANS 4 Sheets-Sheet 2 Filed June 30, 1955 R m. mm

Aug. 28, 1956 B. G. BJALME 2,760,213

INTERCONNECTED CAM PLATES FOR OPERATING CHASERS AND WORK GUIDE MEANSFiled June 30, 1955 4 Sheets-Sheet 3 ,/2 Id I 49 3 a l k INVEN'TOR.

Aug. 28, 1956 s. G. BJALME 2,760,213 INTERCONNECTED CAM PLATES FOROPERATING CHASERS AND WORK cums MEANS.

Filed June 50, 1955 4 Sheets-Sheet 4 IN V EN TOR.

United States Patent INTERCONNECTED CAM PLATES FQR OPERAT- ING CHASERSAND WORK GUIDE MEANS Bengt G. Bjalme, Erie, Pa., assignor to ReedManufactur ing Company, Erie, Pa., a corporation of PennsylvaniaApplication June 30, 1955, Serial No. 519,084

7 Claims. (Cl. 10-122) This invention is a quick opening pipe threaderin which the movement of the chasers from open to closed or threadingposition automatically moves the guides into guiding position andmaintains the guides tight against the pipe under a definite springpressure even though the pipe is over or under size. In a preferredform, the automatic movement of the guides can be disconnected so as topermit manual setting of the guides.

In the drawings. Fig. 1 is a front view of a pipe threader; Fig. 2 is anexploded view; Fig. 3 is a fragmentary edge view; Fig. 4 is a back view;Fig. 5 is a front view of a modification; Fig. 6 is an edge view of theopening and closing device; Fig. 7 is a sectional elevation; Fig. 8 is aback view and Fig. 9 is an edge view showing the connection between theguide and chaser scroll or cam plates.

The threader has a front housing 1 having radial guideways or slots 2for threading chasers 3, a guide housing 4 having radial guideways orslots for guide members 6 and a chaser scroll or cam plate 7 and a guidescroll or cam plate 8 in face to face engagement and interposed betweenthe front housing 1 and the guide housing 4. The front and guidehousings are fixed together and constitute the frame of the threader.The guide cam plate has spirally directed scroll cam members 9 which fitin notches 10 in the guides 6 and move the guides 6 radially inward andoutward as the guide scroll plate 8 is rotated relative to the guidehousing 4. The threading chasers 3 have similar notches 11 whichcooperate with similar scroll cam members on the chaser scroll plate 7so as to move the threading chasers 3 radially inward and outward as thechaser scroll plate is rotated relative to the front housing 1. Thechaser and guide scroll plates 7 and 8 rotate on a bushing 11a boltedbetween the front housing 1 and the guide housing 4. On the fronthousing 1 is an arcuate slot 12 slidably receiving a pivot pin 13 forone of two toggle links 14 and 15. The links have a common pivot 16 andthe link has an extension 17 providing a handle. The pivot pin 13 has athreaded end 18 which extends through the slot 12 and has threadedthereon a clamping nut 19 provided with a handle 20. By loosening thenut 19, the pin 13 may be moved to any selected position along the slot12 and positively locked in that position by tightening the nut whichcan be easily done by means of the handle 20. When the links 14 and 15are aligned with each other and extend in opposite directions from thecommon pivot 16, a pin 20a cooperates with an ear 21 on the chaserscroll plate 7 and moves the chaser scroll plate in a clockwisedirection as viewed in Fig. 2 thereby causing the chasers 3 to moveradially outward to open the die for insertion or removal of pipe. Whenthe handle 17 is turned 180 from the position shown so the links 14 and15 extend in the same direction from the common pivot 16, the'chaserscroll plate is moved;

in a counterclockwise direction thereby causing the threading chasers 3to move radially inward to close the die for threading. The scroll camsurfaces on the chaser 2,760,213 Patented Aug. 28, 1956 ICC and guidecam plates 7 and 8 are centered on the axis of the threader so that inany position of the cam plates, the chasers and guide members arecentered on the axis of the threader. That is, rotation of the camplates moves the chasers and guide members radially but does not changethe concentricity. The parts so far described constitute a quick openingthreader in which the user can select a plurality of pipe sizes by meansof the nut 19 and can open and close the threading chaser by a movementof the handle 17. When the threading chasers are closed, they are inthreading position. When the threading chasers are open, the threadedpipe can be easily and quickly removed from the die without backing thedie ofi the threads. As is customary in such dies, the front housing 1has socket members 22a for receiving handles by which the die may beturned for threading. The parts so far described are or may be of commonconstruction.

In order that the guide member 6 may be moved radially inward andoutward at the same time as the threading chasers 3, the chaser andguide scroll plates 7 and 8 have registering windows or openings 22receiving coil springs 23. At one end of each opening 22, the chaser andguide scroll plates are provided with mating semicyclindricalprojections 24 which act as a seat for one end of the spring 23. At theopposite end of each opening 22, the chaser and guide scroll plates havesimilar mating semi-cylindrical projections 25 which act as a seat forthe opposite end of the spring 23. The spring 23, accordingly, providesthe force transmitting connection between the chaser scroll plate 7 andthe guide scroll plate 8. As the chaser scroll plate 7 is turned in acounterclockwise direction as viewed in Fig. 2, the force is transmittedfrom the projection 24 on the chaser scroll plate through the spring 23to the projection 25 on the guide scroll plate thereby causing a similarmovement of the guide scroll plate 8. While the chaser scroll plate 7should move to a fixed position in the closed position of the die, theguide scroll plate 8 should only move to a position in which the guidemembers 6 tightly engage the outer surface of the pipe 26 as shown inFig. 4. This is permitted by the yieldable connection provided by thespring 23. As soon as the guide members 6 contact the outer surface ofthe pipe 26, movement of the guide members 6 stops, but the continuedmovement of the chaser scroll plate 7 necessary to move the threadingchasers 3 to the proper position continues. There, accordingly, is noneed to have separate adjustments for the pipe. The guides open andclose at the same time as the threading chasers. Furthermore, the guidesare always concentric with the axis of the threader in tight engagementwith the outside of the pipe being threaded. The projections 24 and 25are long enough to remain within the spring 23 in all positions of theguide and scroll plates.

In Figs. 5 to 9, inclusive, is shown another quick opening threaderwhich has the advantage that the guides may be disconnected from themechanism for opening and closing the threading chasers so that the diemay be used for cutting nipples where the portion of the nipples beingthreaded is of different diameter than the portion of the nippleengaging the guides.

In this threader there is a front housing 26 having radial guide slots27 for threading chasers 28. At the back of the housing 26 is fixed ahousing 29 having similar radial slots for guide members 30. Thehousings 26 and 29 are rigidly fixed together and comprise the frame ofthe threader. Journaled on the housing 29 is a chaser scroll plate 31having scroll members 32 fitting in notches 33 in the threading chasers28 so that as the chaser scroll plate 31 is rotated, the threadingchasers 28 are moved radially outward or inward dependingupon the Ydirection of rotation. Rotatable on the guide housing 29 is a guidescroll plate 34 having scroll grooves 35 receiving tangs 36 on theguide: members 30. As the guide scroll member 34 is rotated relative to.the guide housing. 29, the tangs. 36 cooperatewith the scroll slots 35.causing radial inward or outward movement of the guide members dependingupon. direction. of the. rotation- At the outer part. of the. guide.scroll member 34: are sockets 37 receiving springs. 38 arranged betweenthev bottoms of the sockets and: screws 39 threadedv into washers 40which overlap a bearing surface. 41 on: the guide housing 29. Thesprings 38 provide a controlled pressure between. the washers 40 and thesurface. 41 so that the: guide scroll member tends to'remainin position.

For the purpose of adjusting the. threading chasers 28 so as to cutdifierent sizepipe auction the further purpose of opening and closingthe chasers so as: to permit the easy insertion or removal. of pipe, thesame construction.

illustrated inFig. 2 is used.- In accordance: with this construction,the front housing 26- has aslot. 42' receiving. a

pivot pin 43 pivoted to one end of a link. 44. Threaded.

on the pivot pin 43 is a nut 45' provided with a handle 46 so that whenthe nut is loosened, the pivot pin may be moved along the slot 42 toselected. positions for threading different sizes of pipe. When the nut45 is tightened the pivot pin is locked in the selected. position. Theopposite end. of the link 44- is pivoted at. 47 to. a link 48 having anextension 49 providing a handle. The link. 48 has a projection 50 whichfits in an car 51 on the chaser scroll plate 31. These parts are similarin con-- struction to those illustrated by reference numerals 1 2through 21, inclusive, in Fig. 2 andneed not be further described here.In order to provide an operative connection between the chaser scroll.plate. 31 and the guide scroll plate 34, there is provided on the chaserscroll plate two ears 52 between which extend a pin 53 around. which isa coil spring 54 having one end 55 engaging the chaser scroll plate 31and its other end 56. engaging. a catch 57 journaled on the pin 53 andvurging the catch into a notch 58 in the guide scroll member. 34. So longas the catch. 57 is in the notch 58,. the closing of the chaser scrollplate 31 causes a simultaneous closing of. the guide scroll member 34.When the guide members 30 come into contact with the outer surface ofthe pipe being threaded, rotation. of the guide scroll member 34. stopsand the spring 54 permits the continued. rotation of the chaser scrollplate 31 necessary tobring the threading.

chasers 28 into the proper threading position. The. spring- 54 has the.same function as the spring 23 in maintaining, the guides 30 tightlyagainst the outer surface of. the pipe. and in permitting the relativemovement between the chaser and guide SCIOlll plates necessary if theguide scroll. member is to be operated by the. same linkage 43-51,inclusive, which operates the chaser scroll plate.

Under some conditions, for example, in the threading. of nipples, it isdesirable that the guides 30 be independ-- ently adjustable. To achievethis, the catch 57 is moved out of the notch 58 thereby disconnecting.the guide scroll member 34 from the chlaser scroll plate 31. When thisis done, the guides can be independently adjusted, for ex-- ample, toaccommodate a larger diameter surface than that being threaded bythreading chasers 28. It is very easy to manually move the catch 57 outof the notch 58 while the handle 49 is being, turned to close. the dies.It will be noted that there is an inclined section. 59' on each side ofthe notch 58 so that when the catch 57 is released, it is guided backinto the notchas. the handle 49 is turned to rotate the chaser scrollplate 31. The washers 40 provide sufficient friction to hold the guidescroll member 34' in its adjusted position when the catch 57 is out ofthe notch 58.

In both pipe threaders, the guides are set tight against and concentricwith the pipe being. threaded automatically as the die is closed. Thetight fit of the guides is: not. affected by over or under size pipe andprovides the arcan rate alignment necessary to produce straight threads.The tight fit of the guides permits a closer spacing of the guides andchasers thereby decreasing the overall length of the threader.

What is claimed as new is:

1. A quick opening threading die comprising a frame having a first setof angul'arly spaced radial guideways receiving thread cutting chasersand another set of angularly spaced. radial guideways axially spacedfrom the first set receiving guide members, a rotatable chaser cam platehaving spirally directed cam surfaces cooperating with the chasers tomove them radially upon rotation of the chaser plate. relative to' theframe, a rotatable guide cam plate having corresponding spirallydirected cam surfaces cooperating with the guide members to move themradially upon rotation of the guide plate relative to the frame,manually controlled means for rotating the chaser plate relative to. theframe, and a resilient, force transmitting connection from. thechaserplate to the guide plate whereby in closing. the. guide platestopsuponencountering resistance such as that due to contact. of theguide members with-a pipe being threaded. andthe chaser plate continuesrotation to move. the thread. cutting chasers into the proper positionfor threading.

2:. A quick. opening threading die comprising a frame having a.v first.set of angularly spaced radial guideways receiving thread cuttingchasers and. another set of. angularly spaced radial giudeways axiallyspaced from the first set receiving guide members, a rotatable chasercam plate having spirally directed. cam surfaces cooperating. with thechasers to move them radially upon rotation of the chaser plate relativeto the frame,. a rotatable guide cam plate having corresponding spirallydirected cam surfaces cooperating with. the guide. members. to move themradially uponrotation of the guide plate relative to the frame, manuallycontrolled means. for rotating the chaser plate: relative to the frame,opposed angularly spaced. spring seatsv on the chaser and guide plates,a coil spring extending between. said. seats and providing forcetransmitting connection from the chaser plate tothe guide platewherebyin closing the. guide plate stops upon encountering resistance such asthat due to contact of the guide members Withv a; pipe being threadedand the chaser. plate.- continues rotation. to move the thread. cuttingchasers into the proper position for threading- 3.. A quick openingthreading die comprising a front housing having. angularly spaced radialslots. inits. back surface receiving. thread cutting. chasers, anotherhousing fixed. to the. back. of the front housing and having angularl-yspaced. radial slots in its. back surface receiving guide members, achaser plate journaled on said other housing andhavingspirally directedcam. surfacescooperating with the. chasersv to move them. radially uponrotation ofthe plate relative. to the housing, a guide plate likewisejournaled on said other housing and having corresponding spirallydirected cam surfacescooperating with the guide members to move themradially upon rotation of other plate relative to the housing, a flangeon said guide plate extending, over said other housing and presented tothe chaser plate, a catch. cooperating with said flange to compelmovement of the guide plate with the catch, means resiliently mountingthe catch on the chaser plate whereby the catch normlally moves. withthe chaser plate but can move relative. to the. chaser plate wheneverthe guide plate encounters resistance such. asthat due to engagement ofthe. guide. members with the outer surface of a pipe being threaded andmanual means for rotating thev chaser plate relative to the housing toopen. and close the chaser and the guide members.

4. In a quick opening pipe threading die of the type. having. arotatable chaser cam plate for moving a plurality of angularly spacedthread-1 cutting chasers; radially in. equal amounts so the chasers arealways concentric with the axis of. the die, rotatable guide. can platefor a plurality of spaced. guide members:

radially in corresponding equal amounts so the guide members are alwaysconcentric with the axis of the die,-

and further having manual means fior rotating the chaser cam plate, thecombination of a resilient force transmitting connection from the chaserplate to the guide plate whereby in closing the guide plate stops uponencountering resistance such as that clue to contact of the guidemembers with a pipe being threaded and the chaser plate continuesrotation to move the thread cutting chasers into the proper position forthreading.

5. In a quick opening pipe threading die of the type having a rotatablechaser cam plate for moving a plurality of angularly spaced threadcutting chasers radially in equal amounts so the chasers are alwaysconcentric with the axis of the die, rotatable guide cam plate formoving a plurality of angularly spaced guide members radially incorresponding equal amounts so the guide members are always concentricwith the axis of the die, and further having manual means for rotatingthe chaser cam plate, the combination of a catch comprisinginterengaging parts on the chaser and guide cam plates connecting theplates for rotation together, and a resilient connection between one ofthe inter-engaging parts and its associated cam plate whereby rotationof the guide cam plate can stop whenever the guide cam plate encountersresistance such as that due to contact of the guide members with a pipebeing threaded while the chaser cam plate continues its notation to movethe thread cutting chasers into the proper position for threading.

6. In a quick opening pipe threading die of the type having a rotatablechaser cam plat-e for moving a plurality of angularly spaced threadcutting chasers radially in equal amounts so the chasers are alwaysconcentric with the axis of the die, rotatable guide ca-m plate formoving a plurality of angularly spaced guide members radially incorresponding equal amounts so the guide members are always concentricwith the axis of the die, and further having manual means for rotatingthe chaser cam plate, the combination of a latch member on and movablerelative to the chaser cam plate, a cooperating detent part on the guidecam plate, a stop on the chaser cam plate, resilient means on the chasercam plate urging the latch member against the stop and into thecooperating detent part to connect the plates for rota tion togetherwhereby rotation of the guide cam plate can stop whenever the guide camplate encounters re sistance such as that due to contact of the guidemembers with a pipe being threaded while the chaser cam plate continuesits rotation to move the thread cutting chasers into the proper positionfor threading.

7. The construction of claim 3 in which the mounting for the catchcomprises a tangentially directed pin supported between two spacedabutments on the chaser cam plate and in which the catch is bothslidable and notatable on the pin, and further includes a coil springencircling the pin and arranged between one of the abutments and thecatch and urging the catch against the other abutment, said springhaving a part cooperating with the catch to urge it into the notch.

No references cited.

